Communication networks use a physical layer to transmit their respective transmissions between the devices or nodes in the network. This physical layer may be, for example, Ethernet cables, power lines, telephone cables and television cables. For each of the devices on the network to communicate with one another a particular protocol is defined and used by all devices on the network. The protocol substantially defines how data is to be transmitted over the network, what form it should have, how devices can join the network and the like. In the art, the term standard is used interchangeably with the term protocol. Two different networks using the same standard for communication and transmission are said to be networks of the same type. Two different networks, each using a different standard for communication and transmission, are said to be networks of different type. In general, different network types cannot communicate with one another. However, in some cases, two different networks are required to share the same physical layer. This may result in the two networks interfering with the transmissions of one another. Therefore, it would be desirable to enable the use of the same physical layer by two different networks without the networks interfering with the transmissions thereof.
U.S. Pat. No. 7,031,274 to Sherman, entitled “Method for enabling interoperability between data transmission systems conforming to IEEE 802.11 and HIPERLAN standards” is directed towards a method for enabling interoperability between data transmission of Wireless Local Area Network (WLAN) stations operating in different standards, the IEEE® 802.11 and the High Performance Radio Local Area Network (HIPERLAN). In both standards, the WLAN stations access the network via an Access Port (AP). It is desirable that the AP support both standards. According to the method of Sherman, a super-frame which includes a Contention Free Period (CPF) is defined. During the CFP, the AP sends polls to each IEEE® 802.11 station, one at a time, to give them the right to send a packet. Furthermore, the AP sends a spoofing or blocking frame after a determined time period within the CFP. This spoofing frame inhibits IEEE® 802.11 stations from transmitting. In the remaining time period of the CFP the HIPERLAN stations transmit their packets. The IEEE® 802.11 stations see a large CFP with un-detectable transmissions.